Finding the Fourth Proportional to 11,620.55, 17,430.78 and 3,300.57

Step by Step Solution

1. Step 1: Write the proportion equation
   11,620.55 : 17,430.78 = 3,300.57 : x
2. Step 2: Convert to fraction form
   11,620.55/17,430.78 = 3,300.57/x
3. Step 3: Cross multiply
   11,620.55x = 17,430.78 × 3,300.57
4. Step 4: Simplify right side
   11,620.55x = 57,531,509.54
5. Step 5: Solve for x
   x = 57,531,509.54/11,620.55
6. Step 6: Final answer
   x = 4,950.84